Windows Explorer is just lagging, and not showing icons, and crashing

If I select "Date" or "Type" 

windows cursor shows loading?? and then it stalls. sometimes icons will show and then sometimes it just crashes with no icons.

If I try to sort files in any way, it does this.

I used disk management to clear all cache/temp files/thumbnails and rebooted but still.

Thumbnails delaying and not showing is a major issue.